IBM z System After Moore’s Law

The last z System that conformed to the expectations of Moore’s Law was the zEC12. IBM could boast that it had the fastest commercial processor available. The subsequent z13 didn’t match it in processor speed. The z13 chip runs a 22 nm core at 5 GHz, one-half a GHz slower than the zEC12, which ran its 32nm core at 5.5 GHz. Did you even notice?

In 2007 an IBM scientist holds a 3-D integrated stacked chip

In 2015, the z13 delivers about a 10 percent performance bump per core thanks to the latest tweaks in the core design, such as better branch prediction and better pipelining. But even one-half a Ghz slower, the z13 was the first system to process 2.5 billion transactions a day. Even more importantly for enterprise data centers, z13 transactions are persistent, protected, and auditable from end-to-end, adding assurance as mobile transactions grow to an estimated 40 trillion mobile transactions per day by 2025.

IBM clearly isn’t bemoaning the decline of Moore’s Law. In fact, it has been looking beyond silicon for the processing of the future. This week it announced a major engineering breakthrough that could accelerate carbon nanotubes for the replacement of silicon transistors to power future computing. The breakthrough allows a new way to shrink transistor contacts without reducing the performance of carbon nanotube devices, essentially opening a path to dramatically faster, smaller, and more powerful computer chips beyond the capabilities of traditional semiconductors. Guess we can stop worrying about Moore’s Law.

Without Moore’s Law, IBM optimized just about everything on the z13 that could be optimized. It provides 320 separate channels dedicated to drive I/O throughput as well as such performance goodies as simultaneous multithreading (SMT), symmetric multiprocessing (SMP), and single instruction, multiple data (SIMD). Overall about 600 processors (in addition to your configurable cores) speed and streamline processes throughout the machine. Moore’s Law, in effect, has been bypassed. As much as the industry enjoyed the annual doubling of capacity and corresponding lower price/performance it doesn’t need Moore’s Law to meet today’s insatiable demand for processing power.

The company will be doing similar things with the POWER processor. Today we have the POWER8. Coming is the POWER9 followed by the POWER10. The POWER9 reportedly will arrive in 2017 at 14nm, feature a new micro-architecture, and be optimized with CAPI and NVLINK. POWER10, reportedly, arrives around 2020 optimized for extreme analytics.

As IBM explains its latest breakthrough, carbon nanotubes represent a new class of semiconductor materials that consist of single atomic sheets of carbon rolled up into a tube. The carbon nanotubes form the core of a transistor device whose superior electrical properties promise several generations of technology scaling beyond the physical limits of silicon.

The new processor technology, IBM reports, overcomes a major hurdle that silicon and any other semiconductor transistor technologies face when scaling down. In the transistor, two things scale: the channel and its two contacts. As devices become smaller, the increased contact resistance of carbon nanotubes hindered performance gains. The latest development could overcome contact resistance all the way to the 1.8 nanometer node – four technology generations away.

Carbon nanotube chips could greatly improve the capabilities of high performance computers, enabling, for example, big data to be analyzed faster, increasing the power and battery life of mobile devices, and allowing cloud data centers to deliver services more efficiently and economically. Even cognitive computing and Internet of Things can benefit.

Until now, vendors have be able to shrink the silicon transistors, but they are approaching a point of physical limitation, which is why Moore’s Law is running out of steam. Previously, IBM demonstrated that carbon nanotube transistors can operate as effective switches at channel dimensions of less than ten nanometers. IBM’s new contact approach overcomes the contact resistance by incorporating carbon nanotubes into semiconductor devices, which could result in smaller chips with greater performance and lower power consumption.

As transistors shrink in size, electrical resistance within the contacts increases, which limits performance. To overcome this resistance, IBM researchers gave up traditional contact schemes and created a metallurgical process akin to microscopic welding that chemically binds the metal atoms to the carbon atoms at the ends of nanotubes. This end-bonded contact scheme allows the contacts to be shrunken below 10 nanometers without impacting performance. This brings the industry a step closer to the goal of a carbon nanotube technology within the decade, says IBM.

Let’s hope this works as expected. If not, IBM has other possibilities already in its research labs. DancingDinosaur is Alan Radding, a veteran IT analyst and writer. Please follow DancingDinosaur on Twitter, @mainframeblog. See more of his IT writing at technologywriter.com and here.

One Response to “IBM z System After Moore’s Law”

[…] The combination of collaborations and alliances are clearly aimed at establishing Power as the high performance leader for the new generation of workloads. Noted IBM, independent software vendors already are leveraging IBM Flash Storage attached to CAPI to create very large memory spaces for in-memory processing of analytics, enabling the same query workloads to run with a fraction of the number of servers compared to commodity x86 solutions. These breakthroughs enable POWER8-based systems to continue where the promise of Moore’s Law falls short, by delivering performance gains through OpenPOWER ecosystem-driven, full stack innovation. DancingDinosaur covered efforts to expand Moore’s Law on the z a few weeks back here. […]